Clinical outcomes and the impact of valve morphology for transcatheter aortic valve replacement in bicuspid aortic valves: A systematic review and meta-analysis

Background: Bicuspid aortic valve (BAV) is present in approximately 0.5%-2% of the general population, causing significant aortic stenosis (AS) in 12%-37% of affected individuals. Transcatheter aortic valve replacement (TAVR) is being considered the treatment of choice in patients with symptomatic AS across all risk spectra.

Aim: Aim Our study aims to compare TAVR outcomes in patients with BAV versus tricuspid aortic valves (TAV).

Methods: A comprehensive literature search was performed in PubMed, Web of Science, and Cochrane trials. Studies were included if they included BAV and TAV patients undergoing TAVR with quantitative data available for at least one of our predefined outcomes. Meta-analysis was performed by the random-effects model using Stata software.

Results: Fifty studies of 203,288 patients were included. BAV patients had increased 30-day all-cause mortality (odds ratio [OR] = 1.23 [1.00-1.50], p = 0.05), in-hospital stroke (OR = 1.39 [1.01-1.93], p = 0.05), in-hospital and 30-day PPI (OR = 1.13 [1.00-1.27], p = 0.04; OR = 1.16 [1.04-1.13], p = 0.01) and in-hospital, 30-day and 1-year aortic regurgitation (AR) (OR = 1.48 [1.19-1.83], p < 0.01; OR = 1.79 [1.26-2.52], p < 0.01; OR = 1.64 [1.03-2.60], p = 0.04). Subgroup analysis on new-generation valves showed a reduced 1-year all-cause mortality (OR = 0.86 [CI = 0.75-0.98], p = 0.03), despite higher in-hospital and 30-day PPI (OR = 0.1.21 [1.04-1.41], p = 0.01; OR = 1.17 [1.05-1.31], p = 0.01) and in-hospital AR (OR = 1.62 [1.14-2.31], p = 0.01) in the BAV group. The quality of included studies was moderate-to-high, and only three analyses presented high heterogeneity.

Conclusion: TAVR is associated with comparable outcomes in patients with BAV and TAV. Careful selection of BAV cases by preprocedural assessment of valve anatomy and burden of calcification, pre- and post-procedural dilation, and implementing newer generations of valves may improve the safety and efficacy of TAVR in BAV patients.